f2py: Python does not import module

Question

I would like to import an Fortran module into python with f2py .

I successfully compiled the module with the command f2py -c primes.f90 -m primes .

This command generates primes.cp39-win_amd64.pyd and an directory:

primes
--.lib
----libprimes.E32HNUCUWH2OOA5WTEOFP7BSXKY3WIRC.gfortran-win_amd64.dll

When I am trying to import the module as described here with import primes it imports something but not the module. So eg I cannot see the docstring or access the functions.

I suspect that Python tries to import the folder 'primes' and not the module itself.

How can I fix this?

Thanks.

EDIT:

I have used the example from here to demonstrate the problem:

My Python code to showcase the problem:

import primes

print(primes) 
print(primes.__doc__) # should return "This module 'primes' is auto-generated with f2py (version:2). Functions: [...]"
print(type(primes)) # as @VladimirF mentioned should return fortran
print(primes.logical_to_integer.__doc__) # should return "prime_numbers = logical_to_integer(is_prime,num_primes,[n]) Wrapper for ``logical_to_integer``. [...]"

Actual return:

Traceback (most recent call last):
  File "xxx", line 6, in <module>
    print(primes.logical_to_integer.__doc__)
AttributeError: module 'primes' has no attribute 'logical_to_integer'
<module 'primes' (namespace)>
None
<class 'module'>

Edit 1

I have followed up the suggestion of @roygvib. I have tried several versions of python and conda and part of the problem seems the be that I was using the systems interpreter for compiling the module and the conda for running the python code.

For all the other combinations the following exception is raised:

ImportError: DLL load failed while importing primes: Das angegebene Modul wurde nicht gefunden.

can be translated to:

ImportError: DLL load failed while importing primes: The given Module was not found.

So the actual error was that no error was raised in the given combination.

Answer 1

The solution from @zlamere from this github issue worked for me.

instead of f2py -c primes.f90 -m primes I used python -m numpy.f2py -c --fcompiler=gnu95 --compiler=mingw32 primes.f90 -m primes

I don't know why this command works and the other one doesn't.